1. Field of the Invention
This invention is directed to antifriction bearings employing a minimum of space for lubricant containment seals, and providing a desired degree of axial movement without impairing the seal.
2. Description of the Prior Art
Antifriction bearings incorporate seals of various kinds for the purpose of retaining the lubricant while excluding contaminants, whereby the useful life of such bearings can be extended. In considering the prior art there is a big problem of selecting a bearing size that will accommodate the most effective seal for excluding contaminants while retaining the lubricant. Heretofore, bearings have been sized to best accommodate seals that will perform the requirements of lubricant retention and contaminant exclusion. In certain instances where bearings need to be small or down-sized there are limitations which must not be exceeded because of the need for space to receive an effective seal at each end of the bearing assembly. Examples of bearing seals that do not lend themselves to further down-sizing are the following:
Sonnerat U.S. Pat. No. 4,434,985 of Mar. 6, 1984; Christiansen U.S. Pat. No. 4,497,495 of Feb. 5, 1985; Mitsue et al U.S. Pat. No. 4,516,783 of May 14, 1985; and Colanzi et al 4,770,425 of Sept. 13, 1988.
The prior art also includes a SAE Technical Paper Series 871982 on Specification and Seal Development for Passenger Vehicle Wheel Bearings by J. C. M. Bras, dated Oct. 19-22, 1987.